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Re: C language declaration "bugs"

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On 11/10/2016 15:41, Thiago Adams wrote:
> On Tuesday, October 11, 2016 at 11:03:21 AM UTC-3, Ben Bacarisse wrote:
>> Thiago Adams writes:
>
>>> I can't find any options to express dynamic arrays in structs.
>>
>> No, you can't, other than the "struct hack" of putting a flexible array
>> member (i.e. an incomplete array declaration) as the last member.
>
>
> Just to add one more case :
>
> int [] F();
>
> Function returning many int's.
>
> So..when we see
>
> Type* F(); //F singular (GetItem) pointer to one
> Type* F(); //F plural (GetItems) pointer to many

It might be a good idea to have a way of designating a pointer to 
multple elements. But [] is overloaded already.

C however already has a way of doing that:

int (*F())[];    // or:

int (*F())[] {...}

(The last example might look odd, as you don't often see [] just before 
the { of a function body.)

This says the function returns a pointer to an array; pretty much what 
we're after.

Except that hardly anyone who programs in C likes using pointers to 
actual arrays (not in this group anyway). Everyone prefers pointers to 
elements.

Partly, that's because of the awful syntax involved in declaring such 
types and using them.

So, if you need to invent new syntax, it needs to be simpler than array 
syntax. You also have to decide, when p is regular pointer, and q points 
to a multiple, whether p[i] or (p+i) should still be allowed.

For compatibility reasons, it would have to be. But then that means 
three kinds of pointer would be needed:

* Standard C pointer that can target single or multiple objects
* Pointers to single objects
* Pointers to multiple objects

Otherwise there would be little point.

-- 
Bartc

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Thread

C language declaration "bugs" Thiago Adams <thiago.adams@gmail.com> - 2016-10-11 05:17 -0700
  Re: C language declaration "bugs" Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-10-11 13:58 +0100
    Re: C language declaration "bugs" Thiago Adams <thiago.adams@gmail.com> - 2016-10-11 06:47 -0700
      Re: C language declaration "bugs" Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-10-11 15:03 +0100
        Re: C language declaration "bugs" Thiago Adams <thiago.adams@gmail.com> - 2016-10-11 07:41 -0700
          Re: C language declaration "bugs" BartC <bc@freeuk.com> - 2016-10-11 16:31 +0100
        Re: C language declaration "bugs" Keith Thompson <kst-u@mib.org> - 2016-10-11 10:01 -0700
          Re: C language declaration "bugs" Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-10-11 19:10 +0100
  Re: C language declaration "bugs" BartC <bc@freeuk.com> - 2016-10-11 14:14 +0100

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